Genital Pelvis)

Clinical Presentation

A 21-year-old man presents with an absent left testicle.

Fig. 143.1 (A–C) T1- and T2-weighted MRI images reveal the presence of an ovoid mass adjacent to the left external iliac vessels. The mass is hypointense on the T1-weighted image and hyperintense on the T2-weighted image (arrows).

Radiologic Findings

T1- and T2-weighted magnetic resonance (MR) images (Fig. 143.1) reveal the presence of an ovoid mass adjacent to the left external iliac vessels. The mass is hypointense on the T1-weighted image and hyperintense on the T2-weighted image.

Diagnosis

Undescended testis (cryptorchidism)

Differential Diagnosis

Enlarged external iliac lymph node
Aneurysm of the left external iliac artery
Soft tissue mesenchymal tumor

Discussion

Background

Cryptorchidism means “hidden or obscure testis” and generally refers to an undescended or maldescended testis. Although 4% of newborns have undescended testes, the incidence falls to 0.8% by 3 months, as the testis may spontaneously descend after birth.